Recently in Studies Category

Here is an update on California versus overall United States crime rates. The table below shows the rates per 100,000 population for the FBI's violent crime index and property crime index for 2011, nine months of which predates the Realignment program, and 2013, the most recent year with full data available. The data are from the downloaded files on the FBI's Crime in the United States reports for the respective years.

The nation as a whole had a 6% drop in property crime over the two-year period, while California had a 3% increase, a difference of 9%.

Newsflash: Incapacitating people who commit crime has no effect on the amount of crime.

Do you believe that?

A far left advocacy group, the Brennan Center, wants you to. The press release from their latest propaganda (heralded, as ever, as a "study") states:

Increased incarceration had some effect, likely in the range of 0 to 10 percent, on reducing crime in the 1990s. Since 2000, however, increased incarceration had a negligible effect on crime.

Convincing the public that there is little or no relationship between (1) increased incarceration of people who commit crime and (2) enormous crime reduction over the last quarter century is critical to the efforts of the pro-criminal lobby to sell miniaturized sentences (which they understandably call by the opaque name "sentencing reform"). The lobby knows by now -- in part because of its humiliating failure in Congress to pass the Smarter Sentencing Act -- that the public simply is not going to buy slashing sentences as long as it understands that a crook who's in prison is not ransacking your house while you're at work, or selling heroin and similar goodies to your teenager. Hence the effort to convince us that incarcerating criminals has nothing or next to nothing to do with crime reduction -- arguably the most important domestic policy success of the last fifty years.

Related Newsflash: The centuries-long link between crime and punishment just disappeared.

These people are a hoot.

UPDATE: The Heritage Foundation, which takes the same robust pro-"reform" position as the Brennan Center but is a great deal more honest, recently took the view, through its distinguished Fellow, John G. Malcolm, that increased incarceration could be credited with between 25 and 35 percent of the last generation's crime reduction. See Mr. Malcolm's remarks starting at 7:35 of this tape. Somebody's telling a whooper, and it's not John Malcolm.

Natalia Zea reports for CBS Miami on a study of fingerprint match reliability.

The fingerprint examiners correctly matched every single print in the
tests, with only 3 percent of the inaccurate matches caught by a second
examiner, which is part of normal protocol at crime labs across the
country.

That's rather awkward phrasing. Presumably it means that 3 percent of the matches found by the first examiner were not correct but all of the errors were found and corrected on the second examination.

The kerfuffle over the measles vaccine is off-topic for the blog. It is also ultra vires (not virus) for CJLF. I have watched the discussion with some interest, though, particularly the propensity of media outlets of a given orientation to ascribe anti-vaccine beliefs to the other side. Crunching some actual numbers was a fun project (in a nerdy sense of fun) for a soggy Saturday here on the Left Coast, and I found some interesting things about how political orientation relates to an essentially nonpolitical subject.

How many times have we heard "correlation does not prove causation"? Too many to count. How many times have we heard that elementary truth recited and then ignored, as people proceed to argue for policy changes based on correlation alone. Almost as many.

Charlie Wells has this article in the WSJ on financial education of kids and their financial behavior as adults. It has nothing to do with crime, but it sounds a cautionary note about the argument we hear all the time. "Studies show that educational program X is correlated with positive outcome Y. Therefore we must spend more on X to produce Y, and that is more important and more cost effective than the solution only you ignorant rednecks believe in, Z." It does not follow.

Nearly two years ago, we noted a disturbing statistic from half-year preliminary crime data from the FBI. Here is an update from later and more complete data.

Of the categories of crime tracked by the standard statistics, auto theft is the category most likely to have been affected by California's prison realignment program. Auto theft was always a felony. Before realignment, it was therefore a crime for which a state prison sentence was always a possibility, although the judge had discretion to give a lesser sentence. After realignment, auto theft is a crime for which a person can never go to state prison. Not for the 97th offense.

A new study suggests that the microbes present on pubic hair -- which vary from person to person -- could be used as evidence in sexual assault cases. This particular research is in its early stages, so you probably won't hear about genital microbes in a courtroom anytime soon. But the study is just one example of the effort to turn the incredible diversity of the bacteria that live on human beings into a high-tech forensic toolkit.

* * *

The researchers, led by Silvana Tridico from Murdoch University, took scalp and pubic hair samples from seven individuals (three male and four female, with one co-habitating couple in the mix). While hair from the head had around 50 kinds of bacteria a pop, and seemed to be influenced by the environment, pubic hairs had over 70 kinds of bacteria each, which were highly individualized. That's in line with previous studies on the vaginal microbiome, which has shown an unexpected diversity distinguishing one individual from another.

"The advent of DNA profiling has resulted in an increase of sexual offenders using condoms, which they take away, post-assault," Tridico said in a statement. "The implication of this present study is that the transfer of bacteria between victim and offender, in rape cases, may provide a new way of linking the offender to the victim, in instances in which no human DNA is transferred."

The quality of any study cannot be any better than the quality of its data. Modern statistics computer programs can produce a dazzling array of colorful charts and graphs, but if the input data are faulty, it's all pretty nonsense. As we used to say when I was an IT guy, "garbage in, garbage out."

The main source of data for people studying crime has long been the Uniform Crime Reports compiled by the FBI. These numbers are initially reported by local police agencies. There are some known problems and some controversies. Collection and submission of data by the agencies is voluntary. There are even charges of intentional manipulation in some cities.

Then there are the Supplemental Homicide Reports. These provide much more detail on homicides, but compliance is even more spotty. Rob Barry and Coulter Jones report in the WSJ that there are yawning gaps in the data on justifiable homicides by police. For example, Fairfax County, Virginia, did not report justifiable homicides at all because, well, these are crime reports and justifiable homicides are not crimes. Of 105 large police agencies contacted by the reporters, justifiable homicides from 35 of them did not appear in the FBI records at all.

What's a researcher to do? You must know the limitations of your data. I once started a project using the SHR where a key data point was the circumstance of the homicide. I had to shelve it because so many cases had that data point missing that the input data were essentially worthless. Bad research producing very wrong results can be done by people unaware of the limitations of their data. Of course, if the researcher is actually an advocate seeking to bolster the Politically Correct position on a controversy, then truth doesn't matter. Damn the limitations, full speed ahead!

Last week I had this post on the Uniform Crime Reports, and a commenter noted that skepticism was in order due to underreporting by some police departments. Across the pond there appears to be a major kerfuffle on this point. David Barrett reports in the Telegraph:

Almost a million crimes a year are disappearing from official figures as chief constables attempt to meet targets, a study by the police watchdog has disclosed.

Its report exposed "indefensible" failures by forces to record crime accurately, and said that in some areas up to a third of crimes are being struck out of official records.

Her Majesty's Inspectorate of Constabulary said violent crimes and sex attacks were particularly vulnerable to being deleted under "inexcusably poor" systems.

Although the report stopped short of accusing police of widespread "fiddling" it said there was an "undercurrent of pressure not to record a crime across some forces" and "wrongful pressure" by managers.

It means violent criminals and even rapists are not investigated, potentially allowing offenders to strike again.

The FBI has finally come out with the 2013 statistics for Crime in the United States, almost two months later than last year. The good news is that crime is down from 2012 about 5% in crimes per 100,000 population nationwide on both the violent (-5.1%) and property (-4.8%) scales.

Last month, we noted the good news that California crime was down, but we were interested in seeing the national figures for comparison to sort out national trends from possible effects of California's sentencing "realignment." Last year's post making that comparison is here.

We look at property crime as the primary indicator, as persons convicted of violent crimes, either for the present offense or as priors, are not eligible to be shunted off to county jail under realignment. Many property crime convicts are, and given that the jails are overcrowded in most counties they either get released early or they push out other inmates for early release, likely other property crime convicts.

California's overall property crime rate is down less than the national average, -3.8% versus -4.8%. Auto theft is the category tracked by the FBI that is most likely to be affected by realignment, because all auto thefts in 2013 (pre-Prop. 47) were realignment-eligible felonies, while other categories are mixed eligible/ineligible or felony/misdemeanor. Consistent with the realignment-effect hypothesis, California's improvement in auto theft lagged considerably behind the nation, -2.8% versus -4.0%.

Comparing 2010, the last full year before realignment, with 2013, property crime has dropped 7.2% in the nation while rising slightly, 0.8%, in California. Auto theft is down 7.3% nationally but up 5.3% in California.

In the latest issue of the New Yorker, Maria Konnikova has a story that asks, is the field of psychology politically biased? As the popular saying goes, to ask the question is to answer it. Anyone who has spent any time within the field of psychology knows, if they're being honest, that the answer to that question is an emphatic "yes" all around. But what is the nature of the bias?

In almost every debate about policy, someone asserts confidently that "studies show" whatever supports their position. However, what "studies show" is not necessarily so. Occasionally on this blog we highlight why the neat little bottom line result that makes the newspaper may not be true. Sometimes, the reason involves inherent difficulties in studying a particular area, fully disclosed by the researcher, but deemed too complicated for a newspaper article. Sometimes it is simple sloppiness on the part of the researcher. In the worst case, it represents intentional manipulation by an agenda-driven researcher intent on producing "evidence" for a predetermined position.

Eugene Volokh has this comment at VC on a study that purports to show that Supreme Court Justices are more likely to vote for protection of a speaker in First Amendment cases if they are ideologically aligned with that speaker.

Before studiers can crunch numbers, they have to reduce real-world realities to simple numbers. This is called coding and there is a lot of opportunity for either error or distortion in this process.

Wayne Hall of the University of Queensland (Australia) Centre for Youth Substance Abuse Research has a monograph with the above title in the journal Addiction. Here is the abstract:

Aims: To examine changes in the evidence on the adverse health effects of cannabis since 1993. Methods: A comparison of the evidence in 1993 with the evidence and interpretation of the same health outcomes in 2013. Results: Research in the past 20 years has shown that driving while cannabis-impaired approximately doubles car crash risk and that around one in 10 regular cannabis users develop dependence. Regular cannabis use in adolescence approximately doubles the risks of early school-leaving and of cognitive impairment and psychoses in adulthood. Regular cannabis use in adolescence is also associated strongly with the use of other illicit drugs. These associations persist after controlling for plausible confounding variables in longitudinal studies. This suggests that cannabis use is a contributory cause of these outcomes but some researchers still argue that these relationships are explained by shared causes or risk factors. Cannabis smoking probably increases cardiovascular disease risk in middle-aged adults but its effects on respiratory function and respiratory cancer remain unclear, because most cannabis smokers have smoked or still smoke tobacco. Conclusions: The epidemiological literature in the past 20 years shows that cannabis use increases the risk of accidents and can produce dependence, and that there are consistent associations between regular cannabis use and poor psychosocial outcomes and mental health in adulthood.

In olden times, proponents of marijuana prohibition ridiculously exaggerated its harmful effects, a campaign reaching its unintentionally hilarious peak in the film Reefer Madness. Today, proponents of legalization engage in equal and opposite propaganda, trying to convince us that marijuana is completely harmless. I call this campaign Reverse Reefer Madness. CJLF takes no position on the legalization issue, but we should be basing our decisions on science, not propaganda. Hall says:

Our best estimate is that the risk of developing a psychosis doubles from approximately 7 in 1000 in nonusers [102] to 14 in 1000 among regular cannabis users.

Schizophrenia is a terrible disease. It wrecks people's lives. It has a profound impact on the lives of people close to them. Doubling the risk is no trivial matter.

The Heritage Foundation is no longer the devil it once was on the Left. Recently, Heritage has come out strongly for reforming mandatory sentences, and against over-criminalization and over-federalization of law.

I am sympathetic to the latter and skeptical to the former, though I know sentencing reform is backed by very good people and friends like John Malcolm and Paul Larkin at Heritage and Sen. Ted Cruz. Of course it also has the backing of George Soros, the NACDL and the SEIU, which you'd think would scare off anyone to the right of Valerie Jarrett.

This prelude is necessary to equip my friends at Heritage to duck the brickbats headed their way to the effect that, "I always knew you were fascists after all" -- brickbats sure to blacken the sky when Heritage reports that its scholar's extensive study shows:

Based on data from all 50 states from 1978 to 1997, each state execution deters...

Of course deterring the murder of innocent people by executing stone cold guilty ones has never been a big priority with the Left, which has preoccupied itself instead peddling the flabbergastingly false story that blacks are in mortal danger from rampaging whites. They might want to try again, though self-correction -- or any other kind for that matter -- doesn't wear well with the pious (when not snarky) Mark Oslers of the world.

Still, for those who haven't had their brains fried on critical legal studies and other forms of Amerika Stinks theory, the Heritage Study results showing the death penalty's deterrent value will be of more than a little interest.